Each year, about 500 new cases of Wilms tumors are diagnosed in the United States. This number has been fairly stable for many years. About 5% of all cancers in children are Wilms tumors.

Wilms tumors tend to occur in young children. The average age at diagnosis is about 3 years. It becomes less common as children grow older and is uncommon after age 6. It is very rare in adults, although cases have been reported.

Wilms tumors are slightly more common among African Americans and among girls.

Statistics related to survival rates for Wilms tumors are discussed in the section, "How is Wilms tumor staged?"

Last Medical Review: 09/14/2009
Last Revised: 09/14/2009